What are the key features of Windows Server Failover Clustering?

Windows Server Failover Clustering (WSFC) is a feature in Windows Server operating systems that provides high availability and scalability for mission-critical applications and services. Here are the key features of Windows Server Failover Clustering:

1. High Availability: WSFC ensures that critical applications and services remain available even in the event of hardware or software failures. This is achieved by automatically detecting failures and quickly transitioning affected workloads to healthy nodes in the cluster.
2. Automatic Failover: Failover is the process of transferring the responsibility for running a service or application from one cluster node to another in case the original node becomes unavailable. WSFC supports automatic failover, where failover occurs without manual intervention, minimizing downtime and ensuring continuous service availability.
3. Resource Monitoring and Health Detection: WSFC continuously monitors the health of cluster nodes and resources. It detects failures or degradation in resource availability and initiates appropriate actions, such as failover or resource restart, to maintain service availability.
4. Quorum: Quorum is a concept in WSFC that ensures the consistency and integrity of the cluster. It prevents split-brain scenarios where multiple nodes claim to be the primary owner of resources. Quorum is achieved through a voting mechanism among cluster nodes, ensuring that only a majority of nodes can form an active cluster.
5. Clustered Shared Volumes (CSV): CSV is a feature in WSFC that allows multiple cluster nodes to concurrently access shared storage. This enables clustered applications to maintain data consistency and availability while accessing shared storage resources for improved performance and scalability.
6. Cluster-Aware Updating (CAU): CAU is a feature introduced in Windows Server 2012 that simplifies the process of updating clustered servers. It automates the patching process by orchestrating the sequential maintenance of cluster nodes, ensuring that cluster-aware updates are applied with minimal impact on service availability.
7. Dynamic Quorum: Dynamic Quorum is a feature introduced in Windows Server 2012 that adjusts the quorum configuration dynamically based on the current state of the cluster. It allows the cluster to maintain quorum and continue operations even if a significant number of nodes become unavailable, improving resilience and fault tolerance.
8. Cluster-Aware Applications: WSFC supports applications that are designed to be cluster-aware, meaning they can leverage the failover clustering infrastructure for high availability and scalability. These applications can seamlessly failover between cluster nodes without losing data or session state.
9. Integration with Active Directory: WSFC integrates with Active Directory for authentication, authorization, and management purposes. This allows administrators to leverage existing Active Directory infrastructure for managing cluster nodes, resources, and access control.
10. Support for Virtualization: WSFC supports virtualized environments, allowing virtual machines (VMs) to be configured as cluster nodes. This enables organizations to deploy highly available virtualized workloads and applications using technologies like Hyper-V and VMware.